Casingless sausages became known as a substitute for those stuffed into animal-derived casings on the commercial market some years ago. An early example of an effort to supplant animal casings is discussed in the United States Pat. No. 1,009,953, to Boyle, in which sausage meat was placed in a mold that was then submerged in a hot water bath to cook the surface of the meat in contact with the mold so as to produce a thin crust thereon composed of the same meat mixture as the body of the sausages. The imperfections of this method, and ways to improve upon it, are the subject of the Vogt U.S. Pat. No. 1,964,009-011, issued some years later, in 1934. Vogt teaches the production of casingless sausage having an integral protective skin formed of a substantial percentage of nitrogenous or protein matter, that resembles animal-intestine encased sausages, having greater tensile strength than that of a cooked crust of the sausage meat of comparable thickness as taught by Boyle. Vogt's sausage is subjected to a temperature of 120.degree. F or less to form a tender skin that is thereafter toughened by increasing the heat to about 170.degree. F. The United States patent to Paddock U.S. Pat. No. 2,182,211, prepares a casingless sausage by extruding sausage meat through a heat extrusion die. Podebradsky, U.S. Pat. No. 3,063,842, first shapes sausage meat, then freezes the surface of it, then gives a final shaping and compaction, optionally followed by a momentary treatment with a hot compatible liquid.
These and other methods are representative of the art underlying current commercial practices, to the improvement of which the present invention is directed. Significant problems remain unredressed in the prior art at which this invention is aimed:
1. Casingless sausages after packaging have been known to exude fatty oil through their integuments, which is an undesirable property referred to as "oiling off" in the industry.
2. Casingless sausages of the dry-sausage type have been prone to develop blooms of white matter resembling mold, now known to be salt, which greatly impair the salability of the product. This undesirable property is referred to as "salting out" in the industry.
3. Edible casings represent approximately 25% of the cost of the sausage product, and realizing lower costs without sacrificing quality is imperative.
Sausage, whether stuffed into casings, or casingless, contains large amounts of fat, usually in the range of 20%-50%. Oiling-off of the sausage is a problem in both casing and casingless sausage.